The scanning tunneling microscopy and spectroscopy of GaSb1- (x) Bi (x) films of a few-nanometer thickness grown by molecular beam epitaxy
Journal article, 2021

The ultrahigh vacuum scanning tunneling microscope (STM) was used to characterize the GaSb1- (x) Bi (x) films of a few nanometers thickness grown by the molecular beam epitaxy (MBE) on the GaSb buffer layer of 100 nm with the GaSb (100) substrates. The thickness of the GaSb1- (x) Bi (x) layers of the samples are 5 and 10 nm, respectively. For comparison, the GaSb buffer was also characterized and its STM image displays terraces whose surfaces are basically atomically flat and their roughness is generally less than 1 monolayer (ML). The surface of 5 nm GaSb1- (x) Bi (x) film reserves the same terraced morphology as the buffer layer. In contrast, the morphology of the 10 nm GaSb1- (x) Bi (x) film changes to the mound-like island structures with a height of a few MLs. The result implies the growth mode transition from the two-dimensional mode as displayed by the 5 nm film to the Stranski-Krastinov mode as displayed by the 10 nm film. The statistical analysis with the scanning tunneling spectroscopy (STS) measurements indicates that both the incorporation and the inhomogeneity of Bi atoms increase with the thickness of the GaSb1- (x) Bi (x) layer.

semiconductor surface

scanning tunneling microscopy

molecular beam epitaxy


Fangxing Zha

Shanghai University

Qiuying Zhang

Shanghai University

Haoguang Dai

Shanghai University

Xiaolei Zhang

University of Shanghai for Science and Technology

Chinese Academy of Sciences

Li Yue

Chinese Academy of Sciences

Shu Min Wang

Chalmers, Microtechnology and Nanoscience (MC2), Photonics

Jun Shao

Chinese Academy of Sciences

Journal of Semiconductors

1674-4926 (ISSN)

Vol. 42 9 092101

Subject Categories

Materials Chemistry

Other Physics Topics

Condensed Matter Physics



More information

Latest update